Oil cooler



Dec. 9, 1947. J. E. SULLIVAN 2,432,258

OIL COOLER Filed April 3, 1943 IT! M11111! 1 [\N I 1 1| I l [I] I James E Sullivm Patented Dec. 9, 1947 OIL COOLER James E. Sullivan, Dayton, Ohio, assignor to United Arcraft Products, Inc., Dayton, Ohio, a corporation Ohio Application April 3, 1943, Serial No. 481,702

3 Claims. (01. 251-2) This invention relates to heat exchange units, especially for use in cooling hot, viscous liquids such, for example, as the lubricating oil of internal combustion engines, and has particular reference to improvements in heat exchange units of the type comprising, generally speaking, a heat exchange portion in the form of a core which is surrounded by a passageway through which the liquid to be cooled flows prior to entering the core and through which the liquid may how in by-passing relationship to the core in the event that the core may become obstructed to flow of the liquid therethrcugh due to congelation of the liquid contained therein or to any other cause.

One well known form of heat exchange unit of the type referred to and with which the present invention is concerned, comprises a casing enclosing the heat exchange core portion of the unit, and a jacket surrounding said casing and providing a passageway extending therearound. Th jacket is provided at a suitable point, at the top thereof for example, with an opening for the inlet to said'passageway of the liquid to i be cooled, and the casing is provided at a point diametricallyopposite or substantially diametri able point, at the top thereof for example, with an opening for the outlet of the liquid from said passageway. Normally, however, the jacket outlet opening is closed by a valve so that the liquid is prevented from by-passing the core portion of the unit and is required to flow therethrough. Said valve is, however, maintained normally closed by suitable yieldable. means so that it may open under an abnormal pressure in the system of which the heat exchange unit is a part. Accordingly, if the core portion of the unit should become obstructed to fiow of the liquid therethrough due to congelation of the liquid therein, or to any other cause, the pressure in the system will rise until said yieldably closed valve is forced open, whereupon the liquid will flow in by-passing relationship to said core portion until the congealed liquid therein has become decongealed or until such other cause of obstruction to flow through said core portion as may exist has been removed. The valve then will close and flow of the liquid through the core portion will be resumed. The core portion of the unit thus is protected against damage by high pressures in the system such as might arise in the case of an internal combustion engine lubricating system due to starting of the engine following a, period of idleness thereof during which the lubricant in the core portion of the unit may have become congealed, or due to surges of the lubricant resulting from sudden accelerations of the engine.

When the portion of the lubricant or other liquid in the system which is contained in the core portion of the unit is congealed and the remaining hot portion of the lubricant or other liquid in the system is flowing in by-passing relationship to said core portion, it acts to raise the temperature of, and thereby to de-congeal, the congealed liquid in said core portion. De-congelation progresses inwardly toward the center of the core portion of the unit and at an accelerated rate as flow through the core portion is resumed, but maximum efficiency of the unit is not restored until all of the liquid in the core portion is de-congealed. Heretofore, however, the construction of units of the type under consideration has been such that complete de-congelation of the liquid in the core portions thereof has required considerable time, whereas it is quite desirable that complete de-congelation be effected as rapidly as possible.

Accordingly, the general object of thepresent invention is to provide a heat exchange unit of the type under consideration embodying a novel construction whereby the hot portion of the liquid being circulated through the system of which the unit is a part, acts to efiect complete decongelation of congealed liquid in the core portion of the unit far more rapidly than heretofore.

With the foregoing general object in view, the invention consists in a heat exchange unit embodying the novel features of construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawings and defined in the appended claims.

In the accompanying drawings, wherein like characters of reference denote corresponding parts in the different views- Fig. 1 is a side elevation of a heat exchange unit constructed in accordance with one practi cal embodiment of the invention.

Fig. 4 is an enlarged longitudinal section on the line 3-43 of Fig. 2.

Referring to the drawings in detail, i0 designates a casing which contains the heat exchange core portion of the present heat exchange unit,

and ii designates a jacket surrounding said casing and, in conjunction therewith, providing a passageway 11 extending around the outside thereof. 7

The jacket ii is provided at a suitable point, at the top and adjacent to one end thereof, for example, with an opening 52 for the inlet of the liquid to be cooled to the passageway a, while the casing W, at a diametrically opposite or substantially diametrically opposite point, at the bottom thereof, for example, is provided with an opening 13 for the inlet of the liquid to said casing from the passageway a. In addition, the casing i0 is provided at a point'diametrically opposite or substantially diametrically opposite the opening i3, at the top thereof, for example, with an opening i l for the outlet of the cooled liquid from said casing, and the jacket H is provided at a suitable point, at the top thereof, for example, with an opening i 5 for the outlet of the liquid from the passageway a.

Mounted upon the jacket ii in covering relationship to the outlet openings i i and i5 is a housing It in the bottom wall of which are openings Ii and it) which are alined with the openings Hi and i5, respectively, whereby the liquid may flow into said housing either from the casing H] or from the passageway a. The opening i8 normally is closed, however, by a valve l9 so that the liquid cannot flow from the inlet opening l2 through the passageway a and the alined openings i5 and i8 into the housing 55 in by-passing-relationship to the heat exchange core portion of the unit contained in the casing iii, but in its flow to said housing is required to pass through said heat exchange core portion.

As is understood, the present heat exchange unit is to be used in a closed-circuit liquid circulating system such, for example, as the lubricant circulating system of an internal combustion engine employing av Pump, or pumps, for circulating the liquid, and in this connection it will further be understood that a delivery conduit from the engine is connected to the inlet opening i2 and that a return conduit to the engine is connected to an outlet 20 in a wall of the housing i6 so that the liquid is returned to the engine regardless of whether it is being circulated through the heat exchange cor-e portion of the heat exchange unit or'in by-passing relationship to said heat exchange core portion.

The "valve I9 is closed by suitable yieldable means which-exerts a closing force thereon not materially greater than the opening force exerted thereon by the normal pressure of the liquid in the system. Thus, while said valve normally is closed and requires the liquid to flow through the core portion of the unit, it may open andpermit flow of the liquid in by-passing, nondamaging relationship to the core portion of the unit whenever the pressure of the liquid in the system rises above normal. For example, a sudden acceleration of the speed of the engine may produce a sufiiciently high pressure of the liquid to open said valve, or in the event the liquid in the core portion of the unit should become congealed, the pressure in the system obviously will rise until said valve opens.

In accordance with known practice, the casing Iii has extending therethrough numerous openended tubes 2i through which air or any other medium may flow to cool the liquid circulated.

through said casing between said tubes or, alternatively, any other suitable means may be provided for cooling the liquid during its circulation through said casing. Also in accordance with known practice, spaced apart partitions 22 are provided in th casing in for cooperation therewith and with each other to require the liquid to flow in a tortuous path through said casing and to be subjected thoroughly to the cooling effect of the air or other cooling medium flowing through the tubes 2! or their equivalents. In this connection and according to the specific embodiment of the invention illustrated in the drawings, the partitions 22 are disposed horizontally in vertically spaced apart relationship to each other and extend longitudinally of the 13 to the opening M is required to follow a path extending first in one direction and then in the opposite direction longitudinally of the casing progressively from bottom to top thereof through the successive passes, between the partitions, of the single, continuous passageway formed by said partitions.

A heat exchange unit constructed as set forth in the foregoing is known and is highly efficient in normal operation. When, however, the liquid in the heat exchange core portion of such a unit is cold and congealed and the remaining, hot portion of the liquid in the system is circulated in by-passing relationship to said core portion, considerable time is required for the hot, by-passing liquid to effect decongelation of the congealed liquid in said core portion, primarily because the de-congelation progresses only inwardly toward the center of the core portion and because there is no initial direct contact of the hot, icy-passing liquid with the congealed liquid in the core portion.

Since the unit operates at maximum efiiciency only when the core portion thereof is completely iree for circulation of the hot liquid therethrough, it is desirable to completely free said core portion of congealed liquid at the earliest moment possible following initiation of flow of hot liquid in by-passing relationship thereto. The present invention is directed to the accomplishment of this purpose and to that end consists in the provision of means whereby hot liquid may find its way from the passageway a quickly to the central part of the core portion of the unit and may directly contact the central or core portion of v the body of congealed liquid in the core portion 5 mately the middle portion of the casing l0 and which is of double-walled construction with the walls 22' thereof spaced apart to provide a passageway b therebetween. In the casing ill are openings 25 which afford communication between the passageway a and the passageway b, while in either or both of the partition walls 22' are openings 26 for flow of hot liquid from the passageway b into the casing i8 for direct contact with the liquid on said casing. At least some of the openings 28 are located in the central part of one or the other or both of the partition walls 22' so that hot liquid from the passageway b may contact directly with congealed liquid in the central part of the core portion of the unit, Thus, since the hot liquid which is circulated in by-passing relationship to the core portion of the unit when the liquid in said core portion is congealed,

may find its way quickly through the passageway o to the openings 25 and through said openings to the passageway b and thence through the openings 26 into direct contact with the central or core portion of the body of congealed liquid in the casing ill, the de-congelation process progreases outwardly as Well as inwardly and complete de-congelation is efiected rapidly.

Obviously, even in the absence of any openings 26 in either of the partition walls 22' the hot liquid in the passageway b would effect de-congelation far more rapidly than heretofore, By providing the openings 26, however, and thereby providing for direct contact of the hot liquid with the central part of the body of congealed liquid,

de-congelation is eflfected particularly rapidly.

Although the casing ill may have openings 25 in only one side thereto to admit hot liquid from the passageway a into only one side of the passageway b, referably said casing has openings 25 in opposite sides thereof providing communication between opposite side portions of the passageway a and the opposite sides of the passageway I) so that the hot liquid may circulate through said passageway h.

of course, two or more of the partitions 22 may be constructed to operate in the same manner as the single double walled partition described, and in this connection it will be understood that the openings 26 are of small size so that in the normal operation of the system practically all of the hot liquid is required to flow completely through the heat exchange core portion of the unit.

Without fiirther description it is thought that the features and advantages of the invention will be fully understood and appreciated. It is desired to point out, however, that while only a single specific embodiment of the invention has been illustrated and described, the same is readily capable of embodiment in specifically differenta point substantially diametrically opposite said inlet opening an opening for flow of the liquid into the same from said passageway and further having at a point substantially diametrically op- 6 a posite said last mentioned opening an opening for how of the liquid therefrom, said jacket having an outlet opening, a yieldably'closed valve normally closing said jacket outlet opening to require the liquid to circulate through said casing and adapted to open under a hlgher-than-normal pressure in the system to permit the liquid to flow in by-passing relationship to said casing, and partitions in said casing requiring the liquid to follow a tortuous path from end toend of said casing in its flow therethrough, at least one of said partitions comprising spaced apart walls,

' said casing having a restricted opening for flow it the central portion of the liquid path through said casing, said restricted opening into the space between the walls of said partition being considerably smaller than said space.

2. A heat exchange unit for use in a closedcircuit viscous liquid circulating system to cool the liquid during its circulation through the system, said unit comprising a casing having an inlet and an outlet for-the liquid, longitudinally disposed coolant conducting tubes for cooling the liquid during its flow through said casing, means to cause the liquid normally to flow through said casing and to flow in lay-passing relationship thereto when the liquid therein is :ongealed; means defining a passageway exteriorly of and closely adjacent to said casing through which the liquid flows both during its flow to said inlet and during its flow in by-passing relationship to said casing, and partitions in said casing to cause the liquid to flow in a tortuous path from endto end of said casing in its flow therethrough, at least one of said partitions comprising spaced apart walls,said casing having a restricted opening for flow of the liquid from said passageway into the space between said walls and at least one of said partition walls having openings therein adjacent the center thereof for flow of the liquid from the space between said walls into the casing, said restricted opening into the space be- 3. An oil temperature regulator for use in an engine lubrication system and the like wherein theoil is heated in use and circulated under pressure, comprising a plurality of tubes assembled in close parallel relation and open ended for the passage therethrough of a coolant, the oil being caused to flow along and around said tubes whereby to be cooled;- a shell enclosing said tube assembly and formed with oil inlet and oil outlet openings, said shell and said tube assembly constituting the core of the regulator; a jacket spaced from and surrounding said core, said jacket defining a conduit for the delivery of oil to said inlet and for a by-passing how of the oil in the vent of congelation in said core; bailies in said core constraining the oil to follow flow paths parallel to the longitudinal axes of said tubes, at least one of said bailles being of hollow construction and communicating through restricted openings in said shell with said jacket defined and a plurality of openings in said hollow baflle in the approximate center thereof for injectin oil directly into the flow paths of the core, said injected oil being carried along said flow paths from end to end of the core.

' JAMES E. SULLIVAN.

REFERENCES CITED The following referencesare of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Number Number 10 593,062

Dykeman June 21, 1932 

